4.19-stable review patch. If anyone has any objections, please let me know.
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From: Hans de Goede hdegoede@redhat.com
[ Upstream commit c0dc9adf9474ecb7106e60e5472577375aedaed3 ]
Triggers which have trigger specific sysfs attributes typically store related data in trigger-data allocated by the activate() callback and freed by the deactivate() callback.
Calling device_remove_groups() after calling deactivate() leaves a window where the sysfs attributes show/store functions could be called after deactivation and then operate on the just freed trigger-data.
Move the device_remove_groups() call to before deactivate() to close this race window.
This also makes the deactivation path properly do things in reverse order of the activation path which calls the activate() callback before calling device_add_groups().
Fixes: a7e7a3156300 ("leds: triggers: add device attribute support") Cc: Uwe Kleine-König u.kleine-koenig@pengutronix.de Signed-off-by: Hans de Goede hdegoede@redhat.com Acked-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Link: https://lore.kernel.org/r/20240504162533.76780-1-hdegoede@redhat.com Signed-off-by: Lee Jones lee@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/leds/led-triggers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index ec4c957c36b6c..8738fc01523fd 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -125,9 +125,9 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig) flags); cancel_work_sync(&led_cdev->set_brightness_work); led_stop_software_blink(led_cdev); + device_remove_groups(led_cdev->dev, led_cdev->trigger->groups); if (led_cdev->trigger->deactivate) led_cdev->trigger->deactivate(led_cdev); - device_remove_groups(led_cdev->dev, led_cdev->trigger->groups); led_cdev->trigger = NULL; led_cdev->trigger_data = NULL; led_cdev->activated = false;